Yaris 1.8 SR Engine/Gearbox

[mecheng46]

In short, what manual 6speed gearbox model will bolt onto a 2ZR-FE engine with no major or no modifications (EC60)?

I like mending cars etc and I am considering buying an mk2 yaris 1.8 sr which I am assuming it has the 2ZR-FE engine. I went through loads of threads on the internet and most owners are not happy with the performance of the car with some of these people suggesting that it looks like the gearbox gearing is the problem. What makes me think that the gearbox is possibly the problem is because other cars with the same engine haven't got performance issues.

What I am thinking is to change the 5 speed manual gearbox with a manual 6speed gearbox from a different car such as the lotus elise or the corolla, celica etc. Considering the weight of the car i think the most sensible option is a gearbox from a car that uses the toyota 2ZZ-FE or 2ZZ-GE engine.

Does anybody knows if this can be done with no major modifications to the car? Are the engine mountings on the 2ZZ and 2ZR engines the same?